This invention relates to work holding clamp devices.
Many specialized and industrial clamp devices are available that are limited in practical use to workpieces within a certain size range. Examples of some previously known clamps are disclosed in U.S. Pat. Nos: 221,611; 1,259,218; 1,372,833; 2,592,807; 3,092,378; 3,210,070; 3,263,430; and Swedish Pat. No. 137,087.
Even so, a considerable amount of jaw adjustment is required each time material to be clamped is inserted between the jaws of the clamp. Also, release of the material from the clamp involves almost as much time for retraction of the jaws as advancement to the clamping position. Since a force multiplying mechanism is generally required to displace the jaws with the mechanical advantage necessary to exert the requisite holding pressure on the work being clamped, work engaging and releasing operations of the clamp device are slow and time consuming. This creates a production problem in the handling of material undergoing manufacturing processes.